anatomy 10.3

first, systole, increases, pulmonary, aortic, atria, atrioventricular

-during isovolumetric contraction, the (first/second) phase of ventricular (systole/diastole), the ventricular muscles contract and pressure (increases/decreases), but not enough to open the _______ and _____ valves. -blood flows back toward the ____, closing the _________ valves. *FIRST HEART SOUND*

second, systole, increases, semilunar, >, left, right

-during the ventricular ejection phase, the (first/second) phase of ventricular (systole/diastole), contraction (increases/decreases) pressure on the ventricles, pushing open the ____ valves (pressure is (</>) than in pulmonary trunk and aorta). -pressure on the (left/right) ventricle is greater than the (left/right), but the same amount of blood is pumped.

The cardiac cycle comprises a complete relaxation and contraction of both the atria and ventricles and lasts approximately 0.8 seconds. Beginning with all chambers in diastole, blood flows passively from the veins into the atria and past the atrioventricular valves into the ventricles. The atria begin to contract following depolarization of the atria and pump blood into the ventricles. The ventricles begin to contract, raising the pressure within the ventricles. When ventricular pressure rises above the pressure in the two major arteries, blood pushes open the two semilunar valves and moves into the pulmonary trunk and aorta in the ventricular ejection phase. Following ventricular repolarization, the ventricles begin to relax, and pressure within the ventricles drops. When the pressure falls below that of the atria, blood moves from the atria into the ventricles, opening the atrioventricular valves and marking one complete heart cycle.

Describe one cardiac cycle, beginning with both atria and ventricles relaxed.

atrial systole

Most blood enters the ventricle during ________.

closing of the atrioventricular valves

The first heart sound represents which portion of the cardiac cycle?

superior, atrioventricular, increases, ventricles, 70, 80, 100, P, atrial systole

as the atrial muscles contract from the (superior/inferior) portion of the atria toward the _______ septum, pressure (increases/decreases) within the atrium and blood is pumped to the _______ through the open atrioventricular valves. to start, the ventricles are filled with __-__% of their capacity, and atrial contraction contributes the rest. this takes approximately ___ms and is represented by the __ wave. this stage is called _____ _____.

preload, 130

at the end of atrial systole, the EDV, or _____ is about ___ ml of blood in the ventricles

systole

contraction

veins, atria

during diastole (relaxation), blood will flow from the ____ to the ___.

isovolumetric ventricular relaxation phase

first stage of ventricular diastole

isovolumetric contraction

first stage of ventricular systole

S4

heart sound that may indicate failure of the left ventricle

50-60 ml

how much is end systolic volume?

first, diastole, decrease, pulmonary trunk, aorta, dicrotic notch

isovolumetric ventricular relaxation phase, the (first/second) stage of ventricular (systole/diastole), is where the ventricular muscle relaxes, causing pressure on the remaining blood to (increase/decrease). -blood flows back from the ______ _____/_____ pushing on the valves and producing the ______ _____, which is a small dip seen in blood pressure tracings.

second, diastole, less than, atria, ventricles, atioventricular

late ventricular diastole, the (first/second) stage of ventricular (systole/diastole) is where the ventricular pressure eventually is (greater than/less than) in the atria, so blood flows from the ____ into the _____, opening the _____ valves.

S3

may be heard in youth, some athletes and pregnant women

cardiac cycle

period of time that begins with contraction of the atria and ends with ventricular relaxation

diastole

relaxation

late ventricular diastole

second stage of ventricular diastole

ventricular ejection phase

second stage of ventricular systole

S1

sound of closing of the AV valves during ventricular contraction

S2

sound of closing of the semilunar (pulmonary and aortic) valves during ventricular diastole

murmur

usual heart sound caused by turbulent slow of blood, graded 1-6

T, 430

ventricular diastole (relaxation) is represented by the __ wave. there are two phases, and they total ___ ms.

QRS, isovolumetric contraction, ventricular ejection, 270

ventricular systole follows the depolarization of the ventricles and is represented by the ___ complex. it has two phases, ______ ______ and the _____ _____ phase and takes a total of ____ ms.

end systolic volume

volume of blood remaining in each ventricle after systole

diastole, open, closed

when both chambers are in ____, atrioventricular valves are ____ and semilunar valves are ____, the cycle is complete.